Rock drill hole cleansing means



Nov. 30, 1937. E, G. ARHN 2,100,949

ROCK DRILL HOLE CLEANSING MEANS Filed April 26, 1934 2 Sheets-Sheet 1 flfig Nov. 30, 1937. E. cs. GARTIN R OCK DRILL HOLE CLEANSING MEANS Filed April 26, 1934 2 Sheets-Sheet 2 Patented Nov. 30, 1937 nNiTso srarss ROCK DRILL HOLE CLEANSING MEANS Elmer G. Gartin, Claremont, N. H., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application April 26, 1934, Serial No. 722,572

16 Claims.

This invention relates to rock drills, and more particularly to improvements in a rock drill hole cleansing means.

An object of this invention is to provide an improved rock drill hole cleansing means. Another object is to provide in a rock drill of the pressure fluid actuated reciprocating piston type, improved hole blowing means associated with the fluid distributing valve mechanism and hammer piston. Still another object is to provide an improved hole blowing means for supplying pressure fluid to a pressure area on the fluid distributing valve and the opposed pressure areas on the hammer piston, for holding the distributing valve in a hole blowing position and to balance the hammer piston in substantially exhaust closing position within its cylinder so that a hole blowing function is effected in an improved manner. These and other objects will, however, subsequently more fully appear.

In the accompanying drawings there are shown for purposes of illustration two forms which the invention may assume in practice.

In these drawings- Fig. l is a central longitudinally extending sectional view through a rock drilling motor in which the illustrative form of the improved hole blowing means is embodied.

Fig. 2 is a view similar to Fig. 1 showing the valve and hammer piston in a hole blowing position.

Fig. 3 is a fragmentary sectional view showing a portion of the improved hole blowing means.

Fig. 4 is a cross sectional view taken on line 4-4 of Fi 3.

Fig. 5 is a cross sectional view taken on line E5 of Fig. 3.

Fig. 6 is an elevational view of the throttle valve.

Figs. '7, 8, 9 andlO are cross sectional views taken in a plane of line ?'l of Fig. 6 showing the different positions of the throttle valve.

Fig. 11 is a view similar to Fig. 1 showing a modified form of construction.

In the preferred illustrative construction there is shown a rock drill of the hammer type comprising a cylinder i having a bore 2 containing a reciprocable hammer piston 3. This hammer piston has a head portion 4 fitting the cylinder bore and a forwardly projecting striking bar 5 of reduced diameter guided in a bore 6 formed in a front bufier ring 's'. The cylinder I is provided with an enlarged bore 8 in which are arranged a circular rear head and valve chest member 9, a cooperating valve chest member ID, a

ratchet ring H and a rear plate l2, the parts 9, It, I l and [2 being secured within the bore 8 by a rear headblock l3 suitably attached to the rear end of the cylinder. The buffer ring I. is secured within the forward end of the cylinder by a front 5 chuck housing member I4 suitably attached to the forward end of-the cylinder, and rotatably mounted in this chuck housing is a chuck sleeve l carrying a chuck bushing IS in which is mounted the shank ll of a usual hollow rock drill steel. Arranged within the ratchet ring is a ratchet and pawl mechanism l8 of a usual design having a forwardly projecting rifle bar I!) having spiral grooves connected to the spiral lugs of a rifle nut 29 secured within the rear end of the 15 hammer piston. The piston striking bar 5 is provided with longitudinal grooves 2 l engageable with longitudinal lugs formed on a chuck nut 22 secured within the rotatable chuck sleeve l5. As the hammer piston reciprocates within the cylinder, it is rotated by the rifle bar l9 and the rotative movement of the piston is transmitted through the straight grooves on the striking bar through the chuck nut and chuck sleeve to the drill steel. The drill steel is herein formed with a central bore 23 extending therethrough for supplying cleansing fluid to the cutting and of the steel to cleanse the cuttings from-the drill hole. Secured within the rear head block is a gland plug 25 through which cleansing liquid is supplied through a tube 25, extending centrally through axial bores in the rifle bar and hammer piston, to the bore in the drill steel. Further, as the piston reciprocates, pressure fluid is conducted from the forward end of the cylinder bore through the grooves 2| and through the chuck sleeve to the drill steel bore, the cleansing liquid mingling with the pressure fluid as it flows through the steel bore.

The fluid distribution means for supplying pressure fluid to and exhausting fluid from the motor cylinder to efiect reciprocation of the hammer piston herein comprises a valve chamber 26 formed in the member 9, and reciprocable in this valve chamber is an automatic fluid distributing 46 valve 21, herein of the sleeve type, guidedfor reciprocatory movement on a cylindrical guide portion 28 projecting within the valve chamber and formed integral with the valve chest member it. This sleeve valve is provided with an enlarged flange 29 having a rear pressure area 30 and a sleeve portion 3i adapted to fit a bore 32 connecting the valve chamber with the rear end of the cylinder bore. Encircling the valve chamher is a fluid supply groove 33 to which pressure fluid is supplied through passages 34 communicating with an annular pressure chamber 35 formed in the rear head block. Arranged in a bore 33 formed in this head block is a throttle valve 31 having a port 38 for conducting pressure fluid from a central supply passage 39 in the valve to a passage 4|] communicating with the pressure chamber 35. The cylinder is provided with a usual central exhaust passage 4|, and a valve throwing passage 42 communicates with the cylinder 'bore between the rear end of the bore and the exhaust passage 4 I, and this passage is piston controlled and communicates with the valve chamber at the rear side of the valve for supplying pressure fluid to the valve chamber. An exhaust passage 43 connects the rear end of the valve chamber to exhaust. Formed in the valve chamber between the passage 43 and the supply groove 33 is a groove 44 connected by a passage 45 to the forward end of the cylinder bore. As this rock drill structure is of a standard construction, further description thereof is herein deemed unnecessary. 7 7

Now' referring to the improved hole blowing means. associated with the fluid distribution means, it will be noted that formed in the throttle valve 31 is a port 46 having a communicating circumferential groove 41, and this groove is adapted to supply pressure fluid through a passage 48 communicating through a port 49 with the valve chamber, at the rear side of the valve 21. As shownin Fig. 3, the groove 41 is also adapted to supply pressure fluid through a passage 50 communicating, through a restricted port 5|, with the rear end of the cylinder bore at the rear side of the hammer piston.

g The operation of the improved rock drill will be clearly apparent from the description given. When the parts are in the position shown in Fig. 1,

pressure fluid flows through port 38, passage 4!],

chamber 35, passage 34, groove 33 through the bore 32 to the rear end of the cylinder bore, pressure fluid acting on the rear pressure area of the piston head 4 to drive the piston forwardly to effect its working stroke, that is to deliver an impact blow to the shank of the drill steel. Upon initiation of the forward piston movement, the forward end of the cylinder bore is connected to exhaust through the central exhaust passage 4| and the passage 45 communicating with the exhaust passage 43. As the hammer piston moves forwardly, the communication of the exhaust 4| with the forward end of the cylinder bore is cut off by the piston head, while the passage 42 is overrun by the rear edge of the piston, thereby admitting pressure fluid from the rear end of the cylinder bore through passage 42 to the rear end of the valve chamber to act on the rear pressure area 30 of the valve to throw the valve forwardly from the position shown in Fig. 1 to the position shown in Fig. 2. Upon continued forward movement of the piston, the rear edge of the hammer piston overruns the central exhaust 4 I, thereby to connect the rear end of the cylinder bore to exhaust. When the valve is in the position shown in Fig. 2, pressure fluid flows from the supply groove 33 past the valve through the groove 44 and passage v45 to the forward end of the cylinder bore, pressure fluid acting on the forward pressure area of the piston to drive the latter rearwardly to effect its retraction stroke. Upon initiation of rearward piston movement, the rear end of the cylinder bore is connected to exhaust through the central exhaust passage 4|, and, as the piston moves rearwardly, the piston head overruns the exhaust 4|, thereby trapping the pressure fluid within the rear end of the cylinder, compressing the same to a relatively high pressure, and this compression pressure acts on the forward pressure area of the valve to throw the latter rearwardly again into the position shown in Fig. 1, these op-- erations being rapidly repeated during normal operation of the motor.

When it is desired to effect a hole blowing operation, the throttle valve 31 is rotated from the position shown in Fig. 8 to the position shown in Fig. 9, and pressure fluid then flows through passage 48 and port 49 to the rear end of the valve chamber to act on the rear pressure area 39 of the valve to throw the valve forwardly into the position shown in Fig. 2. Pressure fluid at the same time flows through the passage 53 and restricted port 5| to the rear end of the cylinder bore to act on the rear pressure area of the piston to move the piston forwardly. The throttle valve is then turned to the position shown in Fig. 10, thereby to supply pressure fluid through the port 46 to the passage 43, the fluid flowing through the passage 40, supply chamber 35, passages 34 to supply groove 33 past the valve 21 through groove 44 and passage 45 to the forward end of the cylinder bore, the pressure fluid acting on the forward pressure area of the piston to move the piston rearwardly against the opposing pressure flowing through the restricted port 5|, the hammer piston moving rearwardly until the forward edge of the piston head slightly overruns or cracks the central exhaust passage 4 I the pressure within the forward end of the cylinder bore then being substantially reduced by the slight leakage through the exhaust and the fluid flowing through the grooves 2|, on the piston striking bar so that the piston is held by the'pressure fluid flowing through the restricted passage 5|, in a balanced position. It will thus be seen that the fluid distributing valve is held by pressure fluid in its forward position so that pressure fluid flows continuously to the forward end of the cylinder bore and the hammer piston is maintained in a balanced intermediate, substantially exhaust closing. position within the cylinder bore, the piston being held in such position by the pressure on the rear pressure area at the rear side of the piston head acting against the opposing pressure on the front piston area, thereby maintaining the exhaust passage substantially closed. Pressure fluid at this time continuously flows from the forward end of the cylinder bore through the rotation grooves 2| and through the chuck sleeve to the bore 23 in the drill steel to cleanse the cuttings from the drill hole. When it is desired to shut down the motor, the throttle valve 31 is rotated into its neutral or off position shown in Fig. '1, and Fig. 8 shows the position of the throttle valve with the hammer motor running and the hole cleansing means shut 01f.

In the modified form of construction shown in Fig. 11, the rock drill is exactly the same as that described above in the form of the invention shown in Fig. 1, but the hole blowing means, in this instance,'being of somewhat different construction. In the form of the hole blowing means shown in Fig. 11, the passage 49 is omitted, and communicating with the passage 5!; is a passage 33 communicating through a passage 5| formed in the front buffer ring 1 with the interior of the chuck sleeve. When the parts are in the blowing position shown in Fig. 11, pressure fluid flows through the groove 41, passage 50 and restricted passage 5| to the rear end of the cylinder bore to act on the rear pressure area of the piston. The pressure fluid at the same time flows from passage 58 through passages 60 and BI to the interior of the chuck sleeve l5 from which the fluid flows through the bore in the steel to cleanse the cuttings from the drill hole. As the pressure fluid flows through the passage 6| to the interior of the chuck sleeve it, at the same time, leaks past the piston striking bar through the bore 6 in the buffer ring to the forward end of the cylinder bore, and the pressure fluid acts against the forward pressure area of the piston to move the latter rearwardly against the opposing pressure flowing through restricted passage 5|, the piston moving rearwardly until the piston head slightly overruns or cracks the central exhaust passage 4|. The pressure within the forward end of the bore is then substantially reduced, due to the slight leakage through the central exhaust and the fluid flowing through the striking bar grooves, and the pressure acting on the rear pressure area of the piston holds the piston against the opposing pressure acting on the front piston area in a balanced, exhaust closing position substantially midway between the ends of the cylinder during the hole blowing operation. Otherwise this form of the invention is similar to that described above in the preferred form of the invention.

As a result of this invention, it will be noted that an improved hole blowing means is provided for a rock drilling motor whereby the fluid distributing valve and hammer piston are maintained in a hole blowing position in an improved and simplified manner. It will further be noted that an improved hole blowing means is provided wherein the hammer piston is maintained, during the blowing operation, in a position to substantially cut off the communicationof the central exhaust port with the forward end of the cylinder bore so that a continuous flow of pressure fluid is effected from the forward end of the cylinder bore through the bore in the drill steel to cleanse the drill hole.. These and other uses and advantages of the improved hole blowing means will be clearly apparent to those skilled in the art.

While there is in this application specifically described two forms which the invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration and thatthe invention may be further modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a rock drill, a cylinder having a bore, a piston reciprocable therein, fluid supply and distribution means for effecting reciprocation of said piston including a supply passage through which motive fluid is supplied to the distributing means and a piston controlled exhaust port, means for supplying motive fluid simultaneously to the opposite ends of the cylinder bore to act directly on pressure areas at the opposite ends of said piston including a fluid supply passage distinct from said first mentioned fluid supply passage, supply and controlling means for said supply passages operative to effect concurrent motive fluid supply to each of the same, thereby to maintain the piston in a substantially exhaust port closing position substantially midway between the ends of the cylinder, and means for supplying pressure fluid from one end of the cylinder bore, when said piston is insaid substantially midway position, continuously to the drill hole.

2. In arock drill, a cylinder having a bore, a piston reciprocable therein having a grooved striking bar along which cleansing fluid may pass to effect hole blowing, fluid distribution means for effecting reciprocation of said piston including a supply passage through which motive fluid is supplied to the distributing means and a piston controlled exhaust port, means for supplying motive fluid simultaneously to the opposite ends of the cylinder bore toact directly on the pressure area at the rear of the piston and on that at the front end thereof and to the grooved striking bar at the latter end of the piston including a fluid supply passage distinct from said first mentioned fluid supply passage, supply and controlling means for said supply passages operative to effect concurrent motive fluid supply to each of the same, thereby to maintain the piston in a substantially exhaust port closing position between the ends of its cylinder to effect hole blowing, and means for supplying pressure fluid from one end of the cylinder bore, when said piston is in said position, continuously to the drill hole.

3. In a rock drill, a cylinder having a bore, a piston reciprocable therein, fluid supply and distribution meansfor effecting reciprocation of said piston including a supply passage through which motive fluid is supplied to the distributing means and a piston controlled exhaust port, means for supplying motive fluid simultaneously to the opposite ends of the cylinder bore to act directly on pressure areas at the opposite ends of said piston including a fluid supply passage distinct from said first mentioned fluid supply passage, supply and controlling means for said supply passages including a single controlling valve and operative to effect concurrent motive fluid supply to each of the same, thereby to maintain the piston in a substantially exhaust port closing position substantially midway between the ends of its cylinder, and means for supplying pressure fluid from one end of the cylinder bore, when said piston is in substantially midway position, continuously to the drill hole.

4. In a rock drill, a cylinder,- a piston reciprocable therein and having provision for conducting hole blowingfluid from the cylinder, fluid distribution means for effecting reciprocation of said piston including an automatic piston con trolled fluiddistributing valve and a piston controlled exhaust port, and means for effecting a supply of pressure fluid to an area on said valve to holdthe latter in a position for effecting admission to the forward end of said piston, and a concurrent supply of pressure fluid to opposed pressure areas on said piston to maintain the latter in a position in which said exhaust port is substantially closed and said conducting means shall be effective and in which normal valve reversing pressure conditions are not established.

5; In a rock drill, a cylinder, a piston reciprocable therein, fluid distribution means for effecting reciprocation of said piston including an automatic fluidv distributing valve having a throwing passage communicating with the cylinder bore anda piston controlled exhaust port, and hole blowing means including means for efiecting a supply of pressure fluid tothe area on said valve to which said throwing, passage leads and for supplying pressure fluid to opposedpressure areas on the piston to maintain the latter in a position remote from the: forward end of the cylinder and sealing said throwing passage and substantially closing said exhaust port.

6. In a rock drill, a cylinder, a piston reciprocable therein, fluid distribution means for effecting reciprocation of said'piston including an automatic fluid distributing valve having a pressure area on which pressure fluid is adapted to act to effect valve throwing, and hole blowing means including passage means for effecting a supply of pressure fluid to the pressure area on said valve to hold the latter in position for distributing fluid to the forward side of the piston, passage means for supplying pressure fluid directly to the rear end of said piston, and passage means for conducting pressure fluid from said cylinder at the forward end of said piston to the drill hole.

7. In a rock drill, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston and including an automatic fluid distributing valve and a fluid supply connection, and means operative for effecting hole blowing while fluid supply to said distributing valve takes place, and including at least a portion of said valve, for effecting a supply of pressure fluid from said supply connection to the opposed pressure areas on sa-idpiston, to maintain said piston in a relatively stationary position substantially midway between the ends of said cylinder, and passage means for conducting pressure fluid from the forward end of said cylinder, when said piston is in said relatively stationary position, continuously to the drill hole.

8. In a rock drill, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid, from said cylinder for effecting reciprocation of said piston, and means operative to effect hole blowing and including at least a portion of said fluid distribution means for effecting a supply of pressure fluid directly to the opposite ends of said cylinder to act on the opposed pressure areas on said piston to maintain the latter in a relatively stationary hole blowing position substantially midway between the ends of said cylinder, and passage means for conducting fluid from the forward end of said cylinder, when said piston is in said relatively stationary hole blowing position, continuously to the drill hole.

9. In a rock drill, in combination, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to an exhausting fluid from said cylinder for effecting reciprocation of said piston including a free cylinder exhaust port controlled by said piston, and means operative to effect hole blowing and including at least a portion of said fluid distribution means for effecting a supply of pressure fluid directly to the opposite ends of said cylinder to act on the opposed pressure areas of said piston to maintain the latter in a relatively stationary hole blowing position substantially midway between the ends of said cylinder, and passage means for conducting fluid from the forward end of said cylinder, when said piston is in said stationary hole blowing position, continuously to the drill hole.

10. In a rock drill, in combination, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston including a free cylinder exhaust port, controlled by said piston, and means operative to effect hole blowing and including at least a portion of said fluid distribution means for effecting a fluid supply directly to the opposite ends of said cylinder to act on the opposed pressure areas of said piston to maintain the latterin a substantially exhaust port closing position substantially midway between the ends of said cylinder, and passage means for conducting pressure fluid from the forward end of said cylinder, when said piston is in said substantially midway position, continuously to the drill hole.

11. In a rock drill, in combination, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston including an automatic fluid distributing valve having a pressure area, and means operative to effect hole blowing and including at least a portion of said fluid distribution means for effecting a supply of pressure fluid to the pressure area on said valve to hold the latter stationary in one position and to effect a supply of pressure fluid to the opposed pressure areas on said piston to maintain the latter in a relatively stationary hole blowing position substantially midway between the ends of said cylinder, and passage means for conducting pressure fluid from the forward end of said cylinder, when said piston is in said relatively stationary position, continuously to the drill hole. 7

12. In a rock drill, in combination, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston inoludingan automatic fluid distributing valve having a pressure area and a cylinder exhaust port controlled by said piston, and means operative to effect hole blowing and including at least a portion of said fluid distribution means for effecting a supply of pressure fluid to the pressure area on said distributing valve to hold the latter stationary in one position and to effeet a supply of pressure fluid to the opposed pressure areas on said piston to maintain the latter in a substantially exhaust port closing position substantially midway between the ends of said cylinder, and passage means for conducting pressure fluid continuously from the forward end of said cylinder, when said piston is in said substantially midway position, to the drill hole.

13. In a rock drill, in combination, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston including an automatic fluid distributing valve having a pressure area, and means operative to effect hole blowing including a control valve and passage means controlled by said control valve for supplying pressure fluid to the pressure area on said distributing valve to hold the latter stationary in one position and to effect a supply of pressure fluid to the opposed pressure areas on said piston to maintain the latter in a relatively'stationary position substantially midway between the ends of said cylinder, and passage means for conducting pressure fluid continuously from the forward end of said cylinder, when said piston is insaid relatively stationary position, ,to the drill hole,

14. In a rock drill, in combination, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston including an automatic fluid distributing valve having a pressure area and a cylinder exhaust port controlled by said piston, and means operative to eiiect hole blowing including a control valve and passage means controlled by said control valve for supplying pressure fluid to the pressure area on said distributing valve to hold the latter stationary in one position and to effect a supply of pressure fluid to the opposed pressure areas on said piston to maintain the latter in a substantially exhaust port closing position substantially midway between the ends of said cylinder, and passage means for conducting pressure fluid continuously from the forward end of said cylinder, when said piston is in said substantially midway position, to the drill hole.

15. In a rock drill, in combination, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pressure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston including an automatic fluid distributing valve having a pressure area, a cylinder exhaust port controlled by said piston, and passages leading to the ends of said cylinder, and means operative to effect hole blowing including a control valve and passage means controlled by said control valve for supplying pressure fluid to the pressure area on said distributing valve to hold the latter stationary in one position and to effect a supply of pressure fluid to the opposed pressure areas on the piston to maintain the latter in a substantially exhaust port closing position substantially midway between the ends of said cylinder, and passage means for conducting pressure fluid from the forward end of said cylinder, when said piston is in said substantially midway position, continuously to the drill hole, one of said fluid distributing means passages supplying pressure fluid to one pressure area on said piston, and separate passage means for supplying pressure fluid to the opposed pressure area on the piston to hold the latter in said substantially midway position.

16. In a rock drill, a cylinder, a piston reciprocable therein and having opposed pressure areas, fluid distribution means for supplying pres sure fluid to and exhausting fluid from said cylinder for effecting reciprocation of said piston including an automatic fluid distributing valve for controlling the supply of pressure fluid to said cylinder, said valve having a pressure area, and piston controlled exhaust means for said cylinder, means for effecting a supply of pressure fluid to the pressure area on said valve to hold the latter stationary in one position and to supply pressure fluid to said cylinder to act on one pressure area of said piston, and means for supplying pressure fluid to the opposed area on said piston, to maintain said piston in a stationary hole blowing position substantially midway between the ends of said cylinder, and means for conducting fluid, when said piston is in said substantially midway position, continuously from one end of said cylinder to the drill hole.

ELMER G. 'GARTIN.

CERTIFICATE OF CORRECTION. Patent No. 2,100,9 9. November 50, 1957.

ELMER GARTIN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, second column, lines 25, 21; and 25, claim 2, strike out the comma and wgrds '1 and means for supplying pressure fluid fromone end of the cylinder bore,

when said piston is in said position, continuously to the drill hole" and insert the same after "cylinder" in line 22,- same claim; and that the said Letters Patent shouldberead with this correction therein that the' same may conform 'to the record of the 'case in the. Patent Office. Signed and sealed this 1st day of February, A. D. 1958,,

Henry Van Arsdale,

(Seal) I I Acting Commissioner of Patents 

